Apache Subversion (source code), often just called "Subversion" or "SVN", is a source control system implementation.
The SVN book is the free online version of the O'Reilly Version Control with Subversion book.
How to use Subversion (SVN) lays out the basic concepts and provides the first few steps for getting started tracking files.
10 Most Used SVN Commands with Examples is a good refresher list if you've used SVN in the past but it has been awhile since you worked with all the commands.
Searching for a complete, step-by-step deployment walkthrough? Learn more about The Full Stack Python Guide to Deployments book.